The present invention relates to a cooking-and-sterilizing apparatus which can be equally used both in cooking foods by spraying heated aqueous seasoning solutions directly on the foods for cooking and in preparing preservative cooked foods by heating, cooking, and sterilizing the foods that are preliminary sealed in bags or containers.
The inventor developed an apparatus for preparing inert gas-filled packages of preservative cooked foods by putting semi-cooked foods along with seasonings in gas-impermeable bags, replacing the air with nitrogen in the bags, and subjecting the foods stacked in the bags to a series of thermal cooking and sterilizing steps for a short time, and the inventor filed a patent application for claiming the cooking and sterilizing apparatus for a patent (Republished Patent WO95/23526). Also, the inventor developed an apparatus for cooking foods directly by spraying hot aqueous seasoning solutions on raw materials, and the inventor filed a patent application for claiming the cooking apparatus for a patent (Japan Patent Application Laid-Open No. H-11-253311).
These apparatuses, however, can be used exclusively for the sole purpose, and therefore, there has been an increasing demand for an apparatus which can be used commonly both in cooking foods and in preparing preservative cooked foods.
The object of the present invention is to provide a heating, cooking, and sterilizing apparatus which is capable of cooking raw materials directly and of preparing preservative cooked foods.
To attain this object a heating, cooking, and sterilizing apparatus according to the present invention comprises:
a horizontal type of cylindrical heating-and-cooking oven having a door provided on one end for putting in and taking out foods from the inside of the oven;
numerous nozzles arranged on the opposite sides of the inside of the oven and inner-directed toward the center of the oven, which are distributed to numerous branch pipes laid outside of the oven;
a heat exchanger, the inlet of said heat exchanger being connected to the bottom of the oven via a return conduit, and the outlet of the heat exchanger being connected to the nozzles via the branch pipes so that a circulation line may be formed between said heat exchanger and the heat exchanger and the oven;
a circulation pump placed in the circulation line;
first to fourth tanks whose outlets and inlets can be selectively connected to the drawing and discharging sides of said circulation pump;
a compressed air source, a nitrogen gas tank and a vacuum pump, all of which are connected to the oven;
a temperature sensor for detecting inner temperature of the oven, a center temperature sensor for detecting center temperature of foods, and an inner pressure sensor for detecting inner pressure of the oven, all associated with the oven; and
a control section for controlling the temperature and pressure of the oven in response to the signals from the temperature sensors and pressure sensor, and for permitting the inner-directed nozzles to eject aqueous seasoning solutions, hot water, or cooling water according to the software program installed in the control section.
When the apparatus works in the direct cooking mode that cooks foods directly by spraying hot aqueous seasoning solutions on raw materials, for example, the first tank containing an aqueous seasoning solution is connected to the circulation line, and the control section has functions of: allowing the aqueous seasoning solution to circulate in the circulation line; spraying the aqueous seasoning solution on the food in the oven while controlling the inner pressure of said oven and the temperature of the heat exchanger in response to the signals from the temperature sensors and pressure sensor; allowing the aqueous seasoning solution to circulate between the heat exchanger and the oven; and bringing the aqueous seasoning solution back to the second tank after finishing the required cooking.
When the apparatus works in the preservative food-preparing mode that cooks and heat-sterilize prepackaged foods, the third tank is filled with hot water and at the same time the fourth tank is filled with cold water, and the control section has functions of: supplying the oven with the hot water from the third tank, and supplying the oven with the cold water from the fourth tank to cool the oven subsequent to termination of the cooking and sterilizing of the prepackaged foods with heat of the hot water, while controlling the inner pressure of the oven and the temperature of the heat exchanger in response to the signals from the temperature sensors and pressure sensor.